Process of making acetyl cellulose compounds.



tron.

oTro BONHOEFFER, or ELBERFELD, AND HUGO GUNTRUM, OF VOHWINKEL, GERMANY,

ASSIGNORS TO FABBENFABRIKEN- VORM. FBIEDR. BAYER.

OF GERMANY.

GERMANY, A CORPORATION 86 00., OE ELBERFELD,

rnocnss- OF MAKING ACETYL CELLULOSE COMPOUNDS.

Nb Drawing.

' T '0 all whom it may concern:

- fate, etc. 1 1

' aIld HUGO GUNTRUM, doctors Acetyl Cellulose ble-in acetone,

that we, O'r'ro Box HonrrnR of philosophy, chem1sts,'c1t1zens of theGerman Empire, re-

Be it known siding at, respectively,"Elberfeld and Vo-h- Germany have.in-- useful Improvements in winkel, near Elberfeld vented new andCompounds and Processes of, Making Same, a specification.

, Ourpresent invention'relates to the manufacture and production ofacetyl derivatives of cellulose which are distinguished bytheirsolubility in acetone.

The process for their production consists in treating cellulose orparent materials such drid, acetyl chlorid, etc., withthe addition ofacid sulfates (primary sulfates) of primary aromatic amin's, such asanilin bisulgranular powders solua mixture of, acetic ester withamixture of chloroform with mixture of nitrobenzene with They arewhitish alcohol (421'), alcohol and-a alcohol, r

In order toillustrate the new process more fully the following exampleis given, the

parts being by,weight:80 parts of orthotoluidin bisulfate are introducedinto a mix.- ture of 1200 parts of glacial acetic acid and 1000 parts ofacetic acid 'anhydrid. I By heating the mixture to about C. most of thebisulfate enters into solution.

Specification of Letters Patent. Application filed July 19, 1910. SerialNo. 572,737. I

of which" the following is' Subsequently 1 200 parts of cellulose areadded. The cellu- Patented Mar. 28,1911.

loseslowly softens and is totally dissolved aftersome hours. Theresulting "solution possesses great viscosity. It is then furtherstirred at a tem 'oerature below'70" O. until the acetyl-cellulose issoluble inv acetone. To see when this'point is reached a sample of the.mixture is treated with water. the prc cipitate is-filtered ofi, washed,dried and dissolved in acetone. When on repeated testing a solution isobtained, water is added to the whole mass and the precipitatedacetylcellulose is" isolated inthe usual way. It is -a whitish granularpowder soluble in acetone,a mixture of acetic ester with alcohol Y(4:1), a mixture of chloroform with alcohol and a mixture ofnitrobenzene with alcohol.

WVe claim I 1. The process for pounds of cellulose, in treatingcellulose izing agents in the (if-primary described.

2. The process for producing an acetyl compound of cellulose, whichprocess consists in treating cellulose with acetic acid anhydrid in thepresence of ortho-toluidin-bisulfate, substantially as described. Intestimony whereof we have hereunto set our handsin the presence of twosubscribing witnesses.

OTTO BONHOEFF HUGO GU-NTRUM. Witnesses: c

l OH'As. J. W IGHT, ALFRED HENKEL.

producing acetyl comwhich process consists compounds with acetylpresenceof acid sulfates aromatic amins, substantially as I

